English: This paper describes capercaillie (Tetrao urogallus) nest predation in Hedmark County, Norway. The nests were found in spring of 2009. I show that it is possible to find nests in several ways. Of the two methods described, it was more efficient to find nest through niche magazines and local media (newspapers etc.). In addition, pointing dogs were also used in the search for nests to easier dictate which areas I wanted samples from. The 4 dogs and handlers found a total of 7 nests. An increased effort with more pointing dogs searching nests will provide a bigger sample. Of a total of 31 nests, 28 were capercaillie, 1 black grouse, and 1 willow ptarmigan. If one wants to study nest predation in other species than capercaillie, other methods for searching nests should be used. Analysis and estimation of daily survival rate is based on each nests history from the offset of breeding onwards and vegetation measurements after hatching or depredation. To identify predators, game cameras were mounted at some of the nests.

I found that of total 31 nests, 90 % failed hatching. Either predated (80 %) or deserted (10 %) by the female. Of the nests that were predated I got pictures of three incidents of red fox (Vulpes vulpes) and one pine marten (Martes martes). Camera technology and camera mounting technique can be improved to document more cases of predation. Furthermore I found effects of different habitat variables on survival. Decrease in the daily survival rate through the incubation period, may be a result of the females reduced condition and increased activity in the predator regime as their offspring need more nutrition.

The high rate of nest predation in capercaillie may be a consequence of a high food demand of the predator population compared to available nutrition this spring. The four picture series I got of red fox and pine marten implicate that these species are among the most common predators on capercaillie nests in Hedmark. I found: 1) It is possible to collect a sufficient sample of nests by advertising for random findings in niche magazines and local media and furthermore get voluntaries to search with pointing dogs. 2) Improvement of camera technology and mounting technique will result in more documentation of predation. 3) It is plausible to conduct a larger scale study by putting more effort in to nest searching.